Attribute options should be able to update price in percentages

Requesting feature to allow attributes to update the product price by percentages instead of a fixed amount.

I know this is complicated due to the variations in attributes but this feature is essential to e-commerce sites that sell custom products.

I am moderately proficient at PHP and Drupal development so I would be willing to take a crack at writing a patch. However, I would love some feedback from more experienced Uberart developers to understand the best approach to accomplishing this. Feedback and ideas are welcomed.